sequence vs combination

sequence and combination both are nouns.

Word	Noun	Adjective	Verb	Adverb
sequence	Yes	No	Yes	No
combination	Yes	No	No	No

As nouns, combination is a hyponym of sequence; that is, combination is a word with a more specific, narrower meaning than sequence:

sequence: serial arrangement in which things follow in logical order or a recurrent pattern
combination: a sequence of numbers or letters that opens a combination lock

Other hyponyms of sequence include cistron, factor, gene, string, Fibonacci sequence, codon, infinite sequence.

sequence (noun)	combination (noun)
the action of following in order	the act of combining things to form a new whole
film consisting of a succession of related shots that develop a given subject in a movie	the act of arranging elements into specified groups without regard to order
a following of one thing after another in time	a collection of things that have been combined; an assemblage of separate parts or qualities
several repetitions of a melodic phrase in different keys	a group of people (often temporary) having a common purpose
serial arrangement in which things follow in logical order or a recurrent pattern	a sequence of numbers or letters that opens a combination lock
	an alliance of people or corporations or countries for a special purpose (formerly to achieve some antisocial end but now for general political or economic purposes)
	a coordinated sequence of chess moves

sequence (verb)	combination (verb)
arrange in a sequence
determine the order of constituents in